Hold your horses! After further reading it seems to be a limitation from GTA IV itself and Rockstar's refusal to update it.
Go here and read carefully 3rd to 7th posts on the page.
Follow the instructions to create commandline.txt file and then try.
*forums.geforce.com/default/topic/7...dia-geforce-740m-2-gb-graphics-card/?offset=5
There is another official looking page saying similar things here Issues with GTA IV showing video cards with over 2GB as under spec – Rockstar Suppor
This seems pretty much spot on.
I created a commandline text file with this
-norestrictions -nomemrestrict The graphics(the menu photo and the loading photos of the characters) became great but the game never started as it kept on loading maybe as the resource usage was still in red. Then I created a file with
availablevidmem 70.0, didn't use the "-" sign hope thats ok, the resource usage increased and I was able to increase the texture, shadow settings. If I selected the max settings the game became like I was playing it in slow motion. It works fine if only high settings are selected. The graphics on the other hand are not that good. Playable but it hurts your eyes. Is there anything more that can be done? The graphics with -norestrictions -nomemrestrict were awesome.
I have created the text file, do I need to do this-
Note that these command lines can be added immediately after the last quotation mark in the target parameter of the program shortcut.
Locate the shortcut to the video game on your desktop.
Right click the file and select Properties.
Under the shortcut tab, you will see an area that says Target, this will list the exact location of the file within quotation marks.
Modify the Target adding the command line variables after the last quotation mark.
Press apply and start your game via the shortcut.
Issues with GTA IV showing video cards with over 2GB as under spec – Rockstar Suppor